Perhaps you should try some spelling variations:
te sach » toc sach
va hanh » van hanh, va thanh, va danh
cao tuc » dao tuc, cao duc, cao suc
hieu va » hieu qua
tu nano » truc nano
tu nang » tru nang, tu nong, tu lang
cuu tre » cua tre, cau tren, cau treo
tuc va » thuc va, truc va, tuc xa
vi cuu » vi luu, vinh cuu
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ((tu nang) or (tu nano)) x hoi. ((hieu va) OR (lieu va)) cao tuc va hanh vi cuu tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ((tu nang) OR (tu nano)) x hoi. ((hieu va) OR (lieu va)) cao tuc va hanh vi cuu tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ((tu nang) or (tu nano)) x hoi. ((hieu va) OR (lieu va)) cao tuc va hanh vi cuu tre".
• Adding a wildcard symbol may retrieve word variants: te sach ((tu nang) or (tu nano)) x hoi. ((hieu va) OR (lieu va)) cao tuc va hanh vi cuu tre*.